Samenvatting (EN)

Headache is a common complaint during space flights, usually attributed to Space Motion Sickness (SMS). We hypothesize that headache in microgravity represents a separate entity among the secondary headaches attributed to disorders of homeostasis. Objectives: 1) To evaluate prospectively and retrospectively the prevalence and characteristics of headache in microgravity in astronauts/cosmonauts (ESA ILSRA-2009-LoI-0349). 2) To assess the co-existence and relationship of headache episodes and SMS. 3) To evaluate the prevalence and characteristics of headache during simulated microgravity: Bed Rest studies of three different durations (ESA AO-06-BR study). 4) To estimate the correlation between headache episodes during Bed Rest studies and changes in intracranial pressure (ICP) (ESA AO-06-BR study). Subjects 1) Astronauts/cosmonauts participating in current space missions: 20 participants. 2) Astronauts/cosmonauts who participated in space missions during last 15 years ? presumably 50 subjects. 3) Healthy volunteers participating in Bed Rest Studies. Methods 1) Specifically designed headache questionnaires based on the Criteria of the International Classification of Headache Disorders (ICHD-II). 2) Non-invasive intracranial pressure (ICP) measurement using evoked otoacoustic emissions (EOAEs). Results: Classification of space flight induced headache, according to the International Classification of Headache Disorders. Assesment of headache parameters in space and their relationship to SMS. Analysis of correlation between ICP and headache. Taken as a whole, the insight into frequency, characteristics and pathophysiology of headache in microgravity might provide a rationale for developing countermeasures to minimize headache occurrence during the space flight.